The McDermitt caldera (western USA) is commonly considered the point of origin of the Yellowstone hotspot, yet until now no geologic map existed of the caldera and its geology and development were incompletely documented. We developed a comprehensive geologic framework through detailed and reconnaissance geologic mapping, extensive petrographic and chemical analysis, and high-precision 40Ar/39Ar dating. The caldera formed during eruption of the 16.39 ± 0.02 Ma (n = 3) McDermitt Tuff (named here), which is strongly zoned from peralkaline, aphyric, high-Si rhyolite (comendite) to metaluminous, abundantly anorthoclase-phyric, trachydacite, or Fe-rich andesite (icelandite).

This is primarily a GIS-based and Web GIS-based position that will be responsible for producing high-quality maps, data, reports, posters, figures, and other products and will assist in the development/maintenance of web services, maps, and applications. The position will provide services and expertise in the areas of GIS, cartography, graphic design, publications, and web to faculty, staff, students, and clients as well as other duties as assigned.